Leavebuster
Though leaverbuster may have had some effect on reducing the number of trolls/afkers, what it COMPLETELY fails to take into account is the duration of the afk. So far, in my past 20 games, I have had two minor connection issues, which resulted in me closing the client and starting again, due to the attempting to reconnect feature still not working. Although I was only gone from the game for less than three minutes in each case, and the fact that my team was fine with it, I still got placed into the 20 minute low priority queue. It seems that no matter the duration of the dc/afk, leavebuster will stick you in the queue automatically. This can be quite frustrating. Judging by the large amounts of complaints about Leaverbuster on the forums, I don't think I'm the only one with this issue.